1. Field of the Invention
The present invention relates to an antenna terminal board device to be mounted to a UHF tuner and the like.
2. Description of the Prior Art
An example of the terminal board device so far been in use is illustrated in FIGS. 3 to 5, wherein FIG. 3 is an exploded perspective view showing the prior art antenna terminal device, FIG. 4 is an exploded perspective view showing the device before being mounted to a frame body, and FIG. 5 is a cross-sectional view of essential portion of the device mounted to the frame body.
In FIGS. 3 and 4, (31) denotes an antenna terminal body, (32) denotes an antenna pin embedded in the body (31), (33) denotes a coil mount provided on the body (31) perpendicularly thereto, which mount (33) is provided with a protruded portion (34), and an engagement groove (35) is provided on one side face of the body (31). Numeral reference (36) denotes an antenna coil, which is mounted on the mount (33) being wound around the protruded portion (34) with leads (37) at both ends thereof inserted in said antenna pins (32). An antenna resistor (39) is inserted in a holder (38), which is cylindrical and provided with a pulling hole (41) of a lead (40) at one end and an insertion hole (42) for the resistor (39) and a flange (43) at the other end. The antenna resistor (39) with one lead (40) bent is inserted in the holder (38) with the other lead (40) pulled out of the pulling hole (41), and the holder (38) is mounted on the body (31) with its flange (43) inserted in the engagement groove (35). The antenna terminal body (31) and the holder (38) constitute an antenna terminal board device. Incidentally, the other lead (40) of the antenna resistor (39) which has been bent is inserted in one antenna pin (32) together with a lead (37) of the antenna coil (36).
The antenna terminal board device integrally constructed as above is mounted to a frame body (44) of a UHF tuner as shown in FIG. 5, wherein (45) denotes an inductor which electrically couples with the antenna coil (36).
The antenna terminal board device of the prior art as above, however, has various disadvantages as follows:
(1) Since the antenna coil (36) is just turned around the protruded portion (34) of the coil mount (33), the same is liable to be deformed during the assembly work.
Even after the assembly work has been finished, since no means is provided for fixing the turned portion of the coil, the same is liable to get out of position producing a bad effect on the performance.
(2) Since there is provided nothing to protect the antenna coil (36), the same is required to be provided with double insulation in accordance with safety standards. As a result, the external diameter of the coil (36) becomes larger and its forming work becomes harder. Thus, an imperfectly formed coil (36) put on the protruded portion (34) of the mount (33) readily slips out of position.
(3) In the work to insert the antenna resistor (39) into the holder (38), it is necessary to pull out the lead (40) from the hole (41), but the hole (41) is so small that the productivity is kept low.
(4) In mounting the holder (38) to the body (31), the flange (43) of the holder (38) has to be laterally slided with reference to the body (31), which lowers the work efficiency.
(5) There also is a danger for the antenna resistor (39) to get out of the insertion hole (42) at the time the holder (38) is mounted to the body (31).